Non-Enzymatic MGO-Glycation of SRSF2 Drives RNA Mis-Splicing

Area of Science:

• Biochemistry
• Molecular Biology
• Proteomics

Background:

• Methylglyoxal (MGO) is a reactive byproduct of glycolysis accumulating in cancer cells.
• MGO-glycation of proteins is linked to various diseases, including cancer, diabetes, and neurodegeneration.
• A comprehensive understanding of MGO targets and their disease relevance is lacking.

Purpose of the Study:

• To quantitatively map proteome-wide MGO-glycation targets using a novel chemoproteomic approach.
• To investigate the functional consequences of MGO-glycation on specific protein targets, particularly splicing factors.
• To establish a mechanistic link between MGO-glycation and disease pathogenesis.

Main Methods:

• Quantitative chemoproteomic profiling using an alkyne-functionalized MGO probe (AlkMG).
• Site-specific analysis of MGO-glycation on serine/arginine-rich splicing factor 2 (SRSF2).
• Biophysical modeling and experimental validation (RNA pulldown) to assess MGO-glycation effects on protein-RNA interactions and splicing.

Main Results:

• Identified 494 MGO-glycation targets, with many involved in RNA processing pathways.
• Demonstrated that MGO-glycation of SRSF2 destabilizes protein-RNA complexes.
• Showed that MGO-glycation impairs SRSF2 RNA binding and alters RNA splicing, mimicking oncogenic mutations.

Conclusions:

• Glycation is a site-specific regulatory post-translational modification for splicing factors.
• Provides the first evidence of MGO-mediated mis-splicing in living cells.
• Suggests a novel mechanistic link between MGO-glycation and disease progression through altered RNA splicing.